The present disclosure relates generally to a turbine system and more particularly to a micromixer fuel nozzle that may be used with a turbine system.
Some known turbine systems include at least one combustor assembly that mixes compressed air with fuel and ignites the fuel-air mixture to generate combustion gases within a combustion zone defined in the combustor assembly. More specifically, at least some known combustor assemblies use a micromixer that includes an outer sleeve that is oriented to channel air and/or fuel towards the combustion zone and an aft face that is positioned adjacent to the combustion zone. As a result, the aft face is exposed to the relatively high temperatures generated within the combustion zone.
At least some known micromixers channel air and/or fuel towards the combustion zone at a relatively high velocity. Channeling the air and/or fuel at such a velocity ensures that energy losses within the air and/or fuel are minimized, but results in a forced convective cooling of the outer sleeve. As such, thermal gradients and/or thermal stresses may develop within at least some known micromixers. Over cycles, such thermal gradients and/or thermal stresses may limit the useful life of portions of the micromixer and/or may lead to a premature failure of such components.